Founded in 1993 by brothers Tom and David Gardner, The Motley Fool helps millions of people attain financial freedom through our website, podcasts, books, newspaper column, radio show, and premium investing services.

There are probably as many favorite guns among firearms enthusiasts as there are models manufactured. One way to determine what the "best" gun is is to see what people are buying. But that's not a straightforward endeavor.

Since Smith & Wesson Holding(NASDAQ:AOBC) and Sturm, Ruger(NYSE:RGR) are the only publicly traded gunsmiths, we're able to gain some insights into their sales, but mostly of broad categories rather than specific models.

For example, Smith & Wesson reported that fiscal-second-quarter sales were driven 15% higher by demand for its polymer shield and M&P models, while Ruger pointed to demand for its new AR-556 modern sporting rifle and LC9 pistol as reason sell-through from independent distributors to retailers jumped 28% in its last period. But with the bulk of the balance of the industry privately held, it's hard to get a read on who's buying what.

So I turned to GunBroker.com, the world's largest online auction site for firearms and accessories, which every month publishes the five best-selling firearms on its site. While it lists the leaders in every major category of firearms sold, breaking them down between new, used, and a combination of the two, for this list I limited the selection to the five best-selling new, semi-automatic pistols. However, GunBroker.com doesn't list specific numbers for the guns sold. No raw unit totals or total dollar values. So what I did was compile all the monthly lists and broke it down into which gun landed in the top spot the most number of times. Then I looked at which was No. 2 most often; which was third, and so on.

I then arbitrarily assigned a value to each slot. A first-place finish got 5 points; second place, 4 points; third, 3, and so on. I then tallied the results and picked out the top five guns for 2015 (January to November). Nineteen different gun models from eight separate manufacturers appeared on the list. Here are the top five best-selling new semiautomatic pistols on my list, in reverse order.

Fourth Place (tie): Smith & Wesson M&P9 and Sig Sauer P938. Neither gun landed in the top spot over the course of the year, but the models were gun buyers' second and third choices most often. The M&P9 is Smith & Wesson's direct challenge to Glock in the low-cost polymer frame segment and its lightweight design has helped the gunmaker enjoy tremendous growth as handgun sales have taken off.

In contrast, Sig Sauer's P938 is a hammer-fired, single-action semi-auto, with aluminum alloy frame and steel slide. It's super-lightweight and designed for concealed carry.

Third Place: Smith & Wesson M&P9 Shield. This is S&W's answer to the concealed-carry gun niche that is exploding. So popular are its Shield models that during the second quarter the gunmaker produced its one millionth model, which it says makes it "the best-selling personal protection and self-defense pistol" on the market.

Second Place: Taurus PT-111 Millenium G2. Yet another gun designed for the concealed carry market, the Taurus PT-111 is available in 9mm and built on a lightweight polymer platform in a subcompact form factor. Its appearance on the list would surprise many gun enthusiasts, but the fact it was the favorite gun four months in a row probably raised even more eyebrows, though it also attested to the gun's meeting a specific need in the market.

First Place: Kel Tec PMR-30. This might not have been the gun many would have expected to top the list, but the Kel Tec PMR-30 dominated sales at GunBroker.com this year, coming in first place more times than any other model (five), and regularly being a gun buyer's second or third choice. The Kel Tec was also on the top-five list more often than any other model (eight), and unlike Smith & Wesson, Ruger, or Sig Sauer, which each had three different models appear at any time over the course of the year, it was only the Kel Tec PMR-30 that gun buyers wanted.

The Kel Tec PMR-30. Image: Kel Tec Weapons.

What pushes gun enthusiasts to want the Kel Tec is its light weight. Even fully loaded with 30 double-stacked .22 Magnum rounds (.22 WMR), its glass-reinforced nylon Zytel frame is lighter than many polymer-frame guns, yet there's a distinct lack of recoil when fired. It's also pretty accurate.

Gun sales have never been greater. The FBI is on track to conduct more background checks on gun buyers this year than at any other time, even more than the record number of investigations performed in 2013. While GunBroker.com will release its best-selling firearm for 2015 next month, there's a good bet it will be one of those here. And considering how often the Kel Tec PMR-30 has topped the lists so far, I'd be surprised if it wasn't the overall choice of gun buyers everywhere.

Editor's note: A chart detailing the author's methodology has been removed from this article.

Author

Rich has been a Fool since 1998 and writing for the site since 2004. After 20 years of patrolling the mean streets of suburbia, he hung up his badge and gun to take up a pen full time.

Having made the streets safe for Truth, Justice and Krispy Kreme donuts, he now patrols the markets looking for companies he can lock up as long-term holdings in a portfolio. So follow me on Facebook and Twitter for the most important industry news in retail and consumer products and other great stories.